Spray nozzle



T. W. MURPHY SPRAY NOZZLE May 18, 1943.

Filed Aug. 28, 1941 FIG- 7 G I P INVENTOR THOMA W, MURPHY BY A TTORNE Y Patented May 18, 1943 SPRAY NOZZLE Thomas W. Murphy, Penn Valley, Lower Merion Township, Montgomery County, Pa., assignor to Monarch Manufacturing Works, Inc., Philadelphia, Pa., 2. corpcration'of Delaware Application August 28, 1941, Serial No. 408,600

4 Claims.

This invention relates to liquid spray nozzles, and more particularly to liquid spray nozzles adapted to operate under relatively high pressures.

Spray nozzles of the type herein contemplated have numerous applications, such as for powdering milk, wherein it is desired to discharge liquid delivered under high pressures to the nozzle in the form of a spray. Nozzles of this type may b subjected to 3000 pounds pressure per square inch, and must withstand both the excessively high pressures and erosive action to prevent wear at the discharge orifice.

It has heretofore been proposed to form all of the parts comprising the nozzle tip of hard material to resist wear, but due to the hardness of the material there is considerable danger of breakage during assembly of the nozzle parts. Also, strain placed on the nozzle parts during assembly tends to accelerate subsequent breakage at the high pressures to which the nozzle is subjected. Further, even though the nozzle parts are accurately machined to close tolerances a slight amount of dirt assembled into the nozzle may cause a misalignment of the nozzle parts and accelerate the tendency towards breakage.

It is a primary object of my invention to provide a liquid spray nozzle adapted to operate under high pressures, which is highly resistant to wear and breakage.

Another object of my invention is to provide a liquid spray nozzle adapted to operate under high pressures wherein strain during assembly is minimized.

Another object of my invention is to provide a high pressure liquid spray nozzle, which is relatively easy to assemble, and disassemble for cleaning.

'Another object'of my invention is to provide a liquid spray nozzle of the above type having parts which are largely susceptible of manufacture by automatic machine operation.

According to the invention the nozzle body is adapted to be connected to a liquid supply source whereby liquid will be delivered to the nozzle under high pressure." A cap member associated with the nozzle body clamps a holder therebetween which supports an insert of relatively hard material. This insert provides a swirl chamber and a discharge orifice. A-perforated floating disk also formed of relatively hard materialforms the base of the swirl chamber, and admits liquid under high pressure to a space encircling the insert and the liquid is then delivered to the swirl chamber in a manner to effect a whirling or gyratory action of the liquid. The: liquid is delivered from the swirl chamber through the discharge orifice and emerges in the form of a spray.

-I have found that the provision of a floating disk of hard material in combination with an insert of hard material having an orifice, swirl chamber, and inlet slots, and wherein these parts are supported between a body and cap member of relatively softer material provides a nozzle which is highly resistant to wear and breakage.

The drawing illustrates embodiments of the invention and the views therein are as follows:

Figure 1 is a plan view of a spray nozzle embodying my invention,

Figure 2 is a longitudinal sectional view taken along the line 2-2 of Figure 1,

Figure 3 is a plan view of a floating disk I may employ,

Figure 4 is an elevational view of the disk illustrated in Figure 3,

Figure 5 is a bottom plan view of an insert I may employ,

Figure 6 is a longitudinal sectional view taken on the line 66 of Figure 5, and

Figure I is a longitudinal sectional view of a modified form of spray nozzle. which I may employ. V

Referring now to the drawing, and particularly Figures 1 and 2, I have indicated at 10 a generally cylindrical nozzle body which is internally threaded at II to sealingly engage a conduit for supplying liquid under high pressure. The upper end of the body In is provided with a circular recess l2 for receiving a floating disk IS. A generally circular holder I4 is supported on the top face of body l0, and is provided with a reduced neck portion 15 forming an annular shoulder It. A cap member I! threadedly engages body I0 and sealingly clamps shoulder l8 of holder [4 between the body and the cap member.

Holder I4 is centrally bored to receive a cylindrical insert l8 which is preferably press-fitted therein. The insert is has a relatively small and I terial and floating disk I3 is preferably formed of a similar hard material.

- Disk l3 is providedwith a plurality of preferablyconcentric holes 23, and the base of holder I4 is provided with a circular'recess whereby an annular passage 24 formed above disk [3 encircles swirl chamber 2l.

It will be noted that the recess [2 in the upper portion of body it] is of slightly greater depth than the thickness of disk I3 whereby the disk may have a limited floating action. Also, a slight clearance is provided between the side walls of recess [2 and the disk to allow for free movement of the disk. A slight clearance is also provided between the lateral walls of holder l4 and twisting action during assembly are made of hard material that there is considerable danger of breakage. Accordingly, I preferably form the body l0, holder M, and cap I! of relatively soft, unhardened metal.

The operation of the nozzle will now be described. Liquid supplied under high pressure maintains disk 13 in engagement with the base of holder l4 and the base of insert I 8, and at the same time the liquid passes through holes 23 in disk [3 and enters annular passage 24. The liquid is then delivered by slots 22 into swirl chamber 21 and generally tangentially to the walls of the chamber, whereby a whirling motion is imparted to the liquid. The liquid then passes through discharge orifice It! and is discharged from the nozzle in the form of a spray.

Experience has taught that it is impractical to machine the disk, body, and holder to sufficiently accurate tolerances to prevent breakage if they are rigidly engaged, and by employing a construction wherein the disk is permitted a slight floating action the necessity for extremely accurate tolerances is eliminated. Even though a substantially perfect fit might be achieved, a slight amount of dirt on one side of the disk or insert will cause breakage due to misalignment and strain at the high pressures used.

I preferably provide a generally frusto-conical discharge port 25 for the cap member, and preferably have the neck portion [5 of the holder terminate adjacent the initiation of this port. Although the insert 13 is shown as substantially flush with the top face of the holder, I contemplate that the insert may extend slightly beyond the holder, if desired.

Referring now to Figure '1, I have shown a spray nozzle generally similar to that illustrated in Figure 2 but wherein the disk 13 is maintained in engagement with the insert 18 and holder M by a compression spring 21. The nozzle body 23 is formed to provide a seat 29 for the lower convolutions of the spring, and a reduced passage 31 supplies liquid under pressure to the body portion housing the spring 21.

I find that when assembling the nozzle parts securely together to prevent leakage under high pressure operation, the new construction described eliminates all tendency towards breakage from one sided strains due to imperfectly formed surfaces or dirt. Therefore, sufficiently hard and extremely brittle material may be used for the surfaces subject to wear without fear of breakage, th-us prolonging the life of such parts over normally soft core nitrided steel, etc., heretofore used, from roughly eighteen hours to at least two thousand hours based, for instance, on powdering milk with approximately 30% solids which is forced through these sprays under approximately 3000 lbs. pressure per square inch.

The insert and floating disk may be formed of sapphire, fully nitrided steel, or a similar material.

Althoughl have shown and described preferred forms of my invention I contemplate that numerous and extensive departures may be made therefrom without departing from the spirit of my invention and the scope of the appended claims.

The invention is hereby claimed as follows:

1. A high pressure liquid spray nozzle comprising a body of relatively soft material having a passage therethrough and adapted to be connected to a liquid supply source, a holder of relatively soft material engaging the body, an insert of hard material in the holder, the insert having a swirl chamber and discharge orifice therein, a disk of hard material fioatingly mounted between the body and holder, whereby strain between the insert and disk during assembly is eliminated, the disk forming the base of the swirl chamber, and means for conducting liquid to the swirl chamber including slots formed in the insert.

2. A high pressure liquid spray nozzle compris ing a body of relatively soft material having a passage therethrough and adapted to be connectedto a liquid supply source, a cap member of relatively soft material threadedly engaging the body, a holder of relatively soft material clamped between the cap member and body, an insert of hard material in the holder and maintained out of contact with the body and cap member, the insert having a swirl chamber and discharge orifice formed therein, a disk of hard material forming the base of the swirl chamber and floatingly mountedbetween the body and holder, whereby during assembly strain on the insert and disk is eliminated, and means for conducting'liquid to the swirl chamber including slots formed in the insert.

3. A high pressure liquid spray nozzle comprising a body of relatively soft material having a passage therethrough and adapted to be connected to a liquid supply source, a holder of relatively soft material detachably engaged with the body, an insert of hard material in the holder having a swirl chamber and discharge orifice therein, a disk of hard material forming the base of the swirl chamber and terminating laterally outwardly of the insert,- the disk being floatingly mounted between the holder and body, whereby during assembly of the nozzle strain between the insert and disk is eliminated, and means for conducting liquid to the swirl chamber including an annular passage in the holder and slots extending from said passage through the insert to the swirl chamber.

4. A high pressure liquid spray nozzle comprising a body 6f relatively soft material having a passage therethrough adapted to be connected to a liquid supply source, a holder of relatively soft material having an annular shoulder detachably abutting the body, an insert of hard material in the holder disposed substantially axially of said body passage, the insert having a swirl chamber and discharge orifice formed therein, a disk floatingly mounted between the body and holder, whereby strain between the insert and disk during assembly of the nozzle is eliminated, the disk forming the base of the swirl chamber, the holder having an annular passage therein radially outwardly of the insert, the insert having slots formed therein and extending from said annular passage to the swirl chamber, and means for conducting liquid under pressure through the disk to said annular passage.

THOMAS W. MURPHY. 

